Fuselages of aircraft are required to meet safety standards set by a regulatory agency (e.g., the United States Federal Aviation Administration). Typically, the fuselage structures, and the corresponding minimum skin gage, of aircraft are sized by mechanical loading and/or damage tolerance based on regulations and safety criteria. (e.g., Boeing 787 and Airbus A350). Minimum skin gages on larger aircraft to date have sufficient thermal thickness and are sufficiently fire resistant to prevent flame propagation.